Nicolas clement jean brandenburg



(No Model.) Nl C. AJ.. BRANDENBURG.

.MANUPAoTURB-OP SUREWS. Y No. 512,798. Patented Jan. v16,1894

uuuuuuuuuuuuuuuuuuu a annum.

,Ago

' AUNITED STATES PATENT Fries.

SPECIFICATION forming part of vLetters Patent No. 512,798, dated January 16, 1894.

Application tiled December 2, 1892. Serial No. 452.891. (No model.) Patentedin Belgium March 25, 1892,1To. 98,971 in France 'May 5. 1892, No. 221,403, and in England May 5,1892.N0. 8,558.

To all whom it may concern: V

Beit known that I, NIooLAs CLEMENT .I EAN BRANnENBUna-a subject of the King of Belgium, residing at Brussels, (Laeken,) Belgium, have invented certain new and useful Improvements in the Manufacture of Screws, (for which I have obtained Letters Patent in Belgium March 25, 1892, No. 98,971; in France May 5, 1892, No. 221,403, and in England May 5, 1892, No. 8,558;) Yand I do hereby declarev the following to be a full, clear, and exact description of the invention, such as will`enable others skilled in the art to which it appertains to make and use the same, reference being had to the'accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification. l

My invention relates to the manufacture of screws, and has for its object the provision of means whereby more perfect screw threads are obtained than is the case with the usual form of dies.

The invention consists in a novel construction of dies for making screws by the rolling process, as will now be fully described, reference being had to the accompanying drawings, in which- Figure 1 is a face view of one die of a pair, showing its working face. Fig. 2 is an elevation as seen froni'the face, A, D, of Fig. 1. Fig. 3 is a reproduction of Fig. 2 on an enlarged scale in one direction, in order to more clearly show the diiferent planes of the working face of the die, the longitudinal dimension of the die, Fig. 3, being one fourth of, and the transverse dimensions three times the corresponding dimensionsof the die shown in Fig. 2. Figs. 4. to 8 inclusive are sections taken respectively onlines A B, A B', K M, Z V and N P, of Fig. 1, or on lines F. H', W L, X U, and Y O of Fig. 2, said Figs. 4. to 8 inclusive being drawn-to an enlarged scale.

I would state here that'the dimensions of the dies may be varied, and must necessarily be varied according to the dimensions of the screws to be made or the hardness of the metal from which such screws are made, and in Figs. 4 to 8 inclusive'T, T', indicate the projection of the plane described by the axis of the blank when one of the dies is stationary and the other is movable.

each of these sections or portions is strictly parallel with the corresponding section or portion of the co-operative die the two dies being exactly similar but placed in opposite directions, so that the face, E, F, Fig. 2, for example, will be parallel with the corresponding face of the other die, and I have not illustrated the second die in the drawings in order not to complicate the same; fourth, that the parallelism of corresponding counterpart sections or portions is strictly maintained during the relative movement of thedies, because the said movement takes place in guides par- .allel to the plane or face, E, F, Fig. 2, and to the plane T, T', developed by the axis of the blank fifth, that by reason of these geometric arrangements certain of the corresponding sections or portions of the two dies approach or recede from one another during their movement, without, however, 'ceasing to remain,

parallel with each other.

In order that two portions of the corresponding counterpart surfaces shall maintain between them the same distance during the movement, it is necessary that they shall not only be parallel with each other but also with the axial plane T, T', of the blank.

I will now proceed to describe the construction .of the dies, it being understood that to complete a screw the blank has to roll from A B, to C D, or from one end of the dies to the other, when one of said dies is movable, while when both dies move the said blank will revolve about its own axis in situ.

In order that the drawings Fig. l, may be made more clear, the bottom line of the grooves has been omitted, the lines therein shown lindicating the varying width of the cutting edge or face of the teeth.

As shown in Fig. 1, the working face of the dies is divided into four distinct sections.

ICO

The first section, A, B, B A', has no grooves, see also Fig. 4, and serves simply to roll the blank into a perfect cylinder before the thread is formed thereon, and this section may be dispensed with when the blanks are true cylinders. The second section, A B M K, is grooved or toothed, the profile of the teeth being shown in Fig. 5, and the distance between the successive teeth of said section, or from A B to K M, varies but slightly, and this is also the case as to the width of the working or cutting face of said teeth, as shown in Fig. 6, but in the third section of the die, or from K M to P N, the distance between the teeth decreases more rapidly, while the width of the working or cutting faces increases much more rapidly, as shown also in Figs. 7 and S, said Fig. 7 being a section taken about inidway between K M and P N, while in the fourth section, N P C D, the working or cutting face of the teeth increases but slightly in width, while the depth of the grooves or spaces between the teeth is gradually reduced. It will, however, be observed, that the working face of the first section A B, A B', is a plane that is slightly inclined relatively to the plane E E', Fig. 2, that the working or cutting face of the teeth of section A B', K M, lie in a plane A K, of still greater inclination relatively to the plane E' WV, Fig. 2, so that as the blank rolls over or is rolled by said teeth,the latter penetrate into the metal gradually and progressively, forming a helicoidal groove the depth of which nearly approaches that of the finished screw after the blank has reached the end of the second section or the line K, M, Fig. l, while the width of said helicoidal groove is not near that required in the iinished screw, as plainly shown in Fig. 6, which represents a section of die on said line K M, and a section of the screw illustrating the state of its thread. V

It will be observed that during the operation of the teeth ofthe second section on the blank, the point of the latter is not operated upon until said blank has nearly reached the end of the second section or line, K, M. The blank is now operated upon by the teeth of the third section, K M, P N, the operation being completed or substantially so after said blank reaches the point P N. The workin g or cutting faces of the teeth of this section also lie in a plane R Q, Figs. 2 and 3, inclined relatively to the plane NV, Y, the inclination being more rapid or greater than that of sections A B-A B', and A B-K M, and as above stated, the said working orcutting face of the teeth increases much more rapidly in width than those of the precedingsection,the grooves 0r spaces between said teeth decreasing correspondingly both in width and depth, the screw being completed after it reaches the line N P, Fig. l. The work performed by the teeth of this third section consists therefore essentially in spreading laterally the Zones of metal or helical groove or space formed by the teeth of the first section, and also in polishing the bottoms of said grooves and giving then their it has reached the line Z, V, Fig. l, or X U,

Fig. 2, and Fig. 8 illustrates the finished screw i after reaching the line N P, Fig. l, or y O, Fig. 2.

In the fourth section, N P C D, of the die, the working or cutting faces of the teeth also lie in a plane, D N, that is inclined relatively to the plane y F, Figs. 2 and 3, but at an angle thereto, as shown in Fig. 3, so as to facilitate the passage of the screw from between the dies. The'bottom'of the grooves or spaces between the teeth in this fourth section, N, P, C, D, is a prolongation of that of the grooves or spaces in the preceding section, N l? K'L, and lies in a plane D Q, parallel with N D, that is to say, the grooves or spaces are all of the same depth. The gradually decreasing depth of the bottoni of the grooves in the several sections is indicated by the dotted line S R J Q D', in Figs. 2 and 3, while the varying inclined planes in which lie the Working faces of the teeth of said sections is indicated by the full line A A K N D, letter Z indicating the middle portion of the third section, as above set forth. Fin ally, by providing the inclined faces ll B--A BL Ml- U V--O P, Figs. 4: to 8, a longitudinal groove is formed along the dies, the width of which increases from the point of the blank outwardly, so that any particles of metal that may break or be cut from the blank will iind ready egress from between the dies, whereby injury to the thread on the screw is avoided.

The above-described construction presents the following advantages. The blank is first rolled into a perfect cylinder by the first section of the dies. The screw-thread is formed gradually or progressively and all displacement of the blank in the direction of its longitudinal axis is prevented as there is no pressure upon the conical point of the blank until the thread on the body thereof is partially formed; there is a more uniform distribution of the power applied, while as soon as the dies commence the cutting of the point the latter passes through the same stages of operation as the body of the blank. And lastly, all inj ury to the thread cut on the screw is avoided by providing an egress for the chips or cuttings from between the dies below the point of the'blank, as above set forth.

In the drawings l have illustrated a construction of dies more especially designed for the manufacture of wood screws provided with a thread of a given profile, but it will be readily understood that screwshavinga thread of an3r desired profile may be made by simply varying the profile of the teeth of the dies accordingly.

Having thus described my invention, what I claim as new therein, and desire to secure by Letters Patent, is

l. A die for rolling wood screws provided with teeth for forming the screw thread, the

ICO

IIO

working face of the die at the leaving end being inclined in a direction opposite to that of.

the motion ofl'the die.

2. A die for rolling wood screws having a plain surface at the entering end inclined in the direction of motion of the die, zones of substantially parallel teeth inclined to said direction of motion and extending partly into said plain surface, the Working face of each tooth as well as that of the teeth in the difterent zones increasing in width progressively from the entering to the leaving end of the die, the working face at the leaving end inclined in a direction opposite to that of the motion of the die.

3. A die for rolling Wood I vscrews having a plain surface atthe entering end inclined in the direction of motion of the side, a Working face for forming the thread of vthe screw eX- tending partly into said plain surface, the said working face at the leaving end of the die inclined in a direction opposite to that of its motion, and a plain surface inclined in a direction at right angles to the line of motion of the die extending along the Working face, 25

for the purpose set forth.

NICOLAS CLEMENT JEAN BRANDENBURG,

Witnesses:

A. D. OBERCA, T. MORITZ.

It is hereby certi'edthat in Letters Patent No. 512,798, granted January 16, 1894,

'upon the application of Nicolas Clement Jean Brandenburg, of Brussels, Belgium, for

an improvement in the Manufacture of Screws, an error appears in the printed specification requiring the following` correction, viz: On page 3, line 18, the Word side should read die; and that the said. Letters Patent should be read. with this correction therein that the same may conform to the record of the casein the 'Patent Office. A

Signed, countersigned, and sealed this 23d. day of January, A. D. 1894.

JNO. M. REYNOLDS, Assistant Secretary of the Interior.

[SEAL] Gountersigned JOHN S. SEYMOUR,

Commissioner of Patents. 

